Animation in Unity look different than in Blender - rigify addon
You probably have stretched the wing/neck and that's where the exported animation looks different.
Try to avoid squashing or stretching the bones and the problems should be fixed.
If you have an hour or so I have a video that explains why this happens. I recommend watching the whole thing but the squash/stretch problem is covered around 39:32
https://www.youtube.com/watch?v=1Xm1h700uhk